foo.cc: In constructor 'Date::Date(int, int, int)':
foo.cc:6:21: warning: 'Date::year' will be initialized after [-Wreorder]
    6 |     int day, month, year;
      |                     ^~~~
foo.cc:6:14: warning:   'int Date::month' [-Wreorder]
    6 |     int day, month, year;
      |              ^~~~~
foo.cc:8:5: warning:   when initialized here [-Wreorder]
    8 |     Date(int y=2000,int m=1,int d=1):year(y),month(m),day(d){
      |     ^~~~
foo.cc:6:14: warning: 'Date::month' will be initialized after [-Wreorder]
    6 |     int day, month, year;
      |              ^~~~~
foo.cc:6:9: warning:   'int Date::day' [-Wreorder]
    6 |     int day, month, year;
      |         ^~~
foo.cc:8:5: warning:   when initialized here [-Wreorder]
    8 |     Date(int y=2000,int m=1,int d=1):year(y),month(m),day(d){
      |     ^~~~

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